st: FGLS

I want to transform a vector of covariates by dividing it through by
some fitted values (for those familiar with the Amemiya 1977's FGLS
method, it is the typical third step in the procedure, i.e. X/Xb^). My X
in the numerator contains 20 individuals characteristics and I'd like to
find a way to divide through in step so as to avoid the division
manually 20 times. Any help?